2-[123I]-iodolisuride SPET visualizes dopaminergic loss in de-novo parkinsonian patients: is it a marker of striatal pre-synaptic degeneration?
The aim of this study was to assess the correlation between the functional integrity and density of striatal dopaminergic receptors and clinical data in 15 de-novo patients with idiopathic Parkinson's disease by single photon emission tomography (SPET) using 2-[123I]-iodolisuride (ILIS), a tracer based on the D2-dopamine receptor agonist lisuride. Deficient striatal uptake of ILIS correlated with the severity of the disorder, scored by the Unified Parkinson's Disease Rating Scale (UPDRS) (n = 15; ratio of ILIS uptake: basal ganglia/cerebellum [B/C] & UPDRS I-III, Spearman R = -0.562, P = 0.013), Beck's Depression Inventory (BDI) (n = 12; B/C & BDI, Spearman R = -0.825, P = 0.0009) and the ZUNG Depression Scale (ZDS) (n = 11; B/C & ZDS, Spearman R = -0.7425, P = 0.008). Experimental data indicate that lisuride shows a higher affinity for pre-synaptic dopaminergic autoreceptors than for post-synaptic D2-dopamine receptors under conditions of low applied ILIS concentrations as in this study. From the results of this study and these experimental data, we speculate that ILIS-SPET can visualize pre-synaptic striatal dopaminergic degeneration in Parkinson's disease.
Müller
T
T
Department of Neurology, St. Josef-Hospital, Ruhr University of Bochum, Germany.
Eising
E G
EG
Reiners
C
C
Przuntek
H
H
Jacob
M
M
Kuhn
W
W
D000368:Aged; D001921:Brain / Q000000981:diagnostic imaging* / Q000378:metabolism*; D002531:Cerebellum / Q000000981:diagnostic imaging / Q000378:metabolism; D003342:Corpus Striatum / Q000000981:diagnostic imaging / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007457:Iodine Radioisotopes / Q000493:pharmacokinetics; D008090:Lisuride / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D008297:Male; D008875:Middle Aged; D009410:Nerve Degeneration / Q000473:pathology; D009928:Organ Specificity; D010300:Parkinson Disease / Q000000981:diagnostic imaging* / Q000378:metabolism* / Q000503:physiopathology; D012044:Regression Analysis; D013569:Synapses; D014018:Tissue Distribution; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*
D007457:Iodine Radioisotopes; C075786:iodolisuride; D008090:Lisuride; D004298:Dopamine